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United States Patent | 6,037,459 |
Cummins ,   et al. | March 14, 2000 |
A method for the generation of ammonia from dinitrogen is provided including reacting a three coordinate, low oxidation state transition metal complex with dinitrogen under substantially atmospheric pressures to obtain a metal-nitrido complex, whereby the oxidation state of the metal complex increases, and reducing the metal of the metal nitrido complex in the presence of a hydrogen source, so as to obtain NH.sub.3. A novel metal complex is provided which is capable of cleaving small molecules which includes a metal selected from the group consisting of molybdenum, titanium, vanadium, niobium, tungsten, uranium and chromium. The compound may have the formula M(NR.sub.1 R.sub.2).sub.3 where M is a transition metal; R.sub.1 and R.sub.2 are independently selected from the group consisting of tertiary alkyls, phenyls and substituted phenyls. The compound permits cleavage of nitrogen--nitrogen triple bonds.
Inventors: | Cummins; Christopher C. (Cambridge, MA); Laplaza; Catalina E. (Somerville, MA) |
Assignee: | Massachusetts Institute of Technology (Cambridge, MA) |
Appl. No.: | 841283 |
Filed: | April 29, 1997 |
Current U.S. Class: | 534/11; 423/352; 556/42; 556/51; 556/57 |
Intern'l Class: | C07F 005/00; C07F 007/28; C07F 009/00; C07F 011/00 |
Field of Search: | 556/42,51,57 423/351,352 534/11 |
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